The present invention relates to a chamber according to the preamble of claim 1, to a chamber combination according to the preamble of claim 2, to a vacuum treatment facility according to the preamble of claim 12 as well as to a transport method according to the preamble of claim 13.
For the transport of workpieces, particularly of storage disks, such as CD""s, magnetic or magneto-optic storage disks, in a chamber of a vacuum treatment facility, for example, for the treatment of the workpieces by reactive or non-reactive vacuum processes, such as etching processes, physical or chemical coating processes with or without glow discharge support, it has been known for a long time to provide a plurality of workpiece receiving devices which can be rotated jointly about an axis in an alignment with provided exterior openings of the chamber. Reference can be made in this respect to U.S. Pat. No. 3,856,654 or German Patent Document DE-PS 24 54 544.
According to U.S. Pat. No. 3,856,654, it is known to rotate frame-type workpiece receiving devices in the chamber about an axis in the manner of a carrousel. When a frame containing the workpiece has reached the alignment position with the exterior opening of the chamber on which a working station is mounted, the workpiece is pushed into the treatment position by means of a lifting element which operates in parallel to the axis of rotation. This resulted in a three-dimensional displacement path for the workpieces, specifically in two dimensions according to the plane of rotation of the carrousel and in a third dimension, in parallel to the axis of rotation of the carrousel out of the chamber.
German Patent Document DE-PS 24 54 544 suggests a configuration in which the displacement path in the third dimension is reduced considerably in order to achieve a more compact construction of the facility. For this purpose, the workpieces are displaced in the treatment position only slightly in parallel to the axis within the framework of the suspension by means of which workpiece receiving frames are disposed on the rotating carrousel so that they can be displaced in the axial direction. For this purpose, a ram, which is mounted to be aligned with the respective exterior opening with the treatment station, engages on the workpiece holding frame, opposite the treatment chamber. Thus the wall of the treatment station mounted to the exterior opening of the chamber is completed by means of a part rotating with the carrousel.
In the case of the facilities according to German Patent Documents DE-OS 39 12 295, 40 09 603, 37 16 498 and European Patent Document EP-A 0 389 820, this principle is also pursued in partially constructive variants.
However, in the manufacturing processes, particularly of the above-mentioned circular-disk-shaped workpieces, it becomes more and more necessary to carry out a plurality of individual treatment steps on a corresponding number of treatment stations. The approach in which the workpieces in the treatment position were lifted only minimally on the transport plane of the workpiece holding carrousel is only a limited remedy in this case because the available space on the chamber with the carrousel is limited.
It is a first object of the present invention to solve this problem based on a chamber with a carrousel-type conveyer of the type indicated in the preamble of claim 1.
The characterizing part of claim 1 of the invention achieves this purpose.
In addition to the plurality of workpiece receiving devicesxe2x80x94the carrouselxe2x80x94disposed so that they can be rotated about an axis, a transport element is provided which can be moved out and back at least in one motion component radially to the above-mentioned axis in a controlled manner and which is disposed in the chamber independently of the carrousel. As a result, it becomes possible to particularly radially move the workpiece back and forth at given rotating positions, specifically when a receiving device on the carrousel is aligned with one of the exterior openings of the chamber to be serviced, with a stroke that can be selected according to the circumstances so that, starting from the carrousel, the workpieces can be conveyed through the exterior openings and nevertheless, in the event of an only radial movement, the two-dimensionality of the transport path is fully maintained and in the event of a movement of the transport element that is only partially radial, if desired, the extent of the transport movement in the third dimension can be selected arbitrarily. Since the carrousel diameter is determined by the size and mainly by the number of its workpiece receiving devices, and the axial dimension of the chamber does not affect this possible number, according to the invention, the linear stroke of the transport element is placed in a plane of the chamber which is large as a result of the number. Thus, without any enlargement of the chamber, space is available for a long transport stroke.
With respect to a second object of the invention, it was recognized that it is an additional disadvantage of the previously known carrousel transport techniques that additional elements are provided on the chamber in order toxe2x80x94even though partially to a minor extentxe2x80x94transport the workpieces from the carrousel transport plane in the direction of the respective treatment stations. The providing of such additional elements particularly stands in the way of a flexible conception of facilities of different configurations that is adapted to the requirements because of the fact that the interaction of the carrousel and the additional elements is aimed at the respective chamber configuration with its specifically provided exterior openings.
If, for example, in such a configuration of the facility, one of the provided exterior openings is not lined up with a treatment station but is closed by means of a cover, the additional transport element must nevertheless be provided and assigned to this opening in order to be able to use the same chamber in a different configuration of the facility.
Based on these above-mentioned previously known chambers, it is an object of the invention to provide a chamber in the case of which the mutual physical arrangement of the exterior openings with respect to an axis of rotation about which, in this case, at least one workpiece receiving device rotates, can be selected arbitrarily within wide limits and/or which provides the possibility of being able to construct overall facilities to be extremely compact while the efficiency is high.
This object is achieved in the German Patent Application P 41 17 969.2 with parallel applications in Europe No. 92 108 771.4, in the U.S. Ser. No. 07/888 111, in Japan No. 4-140 357. A chamber is described there in the case of which the workpiece receiving devices are arranged on a transport element which, as a whole, is disposed to be driven about the axis in a rotationally movable manner and which, in addition, can be linearly moved and moved back with respect to this axis. This can significantly increase the compactness of treatment facilities of this type if, according to the second aspect of the present invention, an approach according to claim 2 is followed which also significantly increases the constructive degree of freedom.
In a preferred chamber combination according to FIG. 3, a chamber according to claim 1 is provided as an additional chamber, that is, a chamber comprising the workpiece receiving carrousel and a radially operable transport element which is disposed independently of it.
In the case of the latter chamberxe2x80x94the xe2x80x9ccarrousel chamberxe2x80x9dxe2x80x94whether separately or in the above-mentioned combination, it is preferably suggested according to claim 4 that the sport element which is disposed independently with respect to the plurality of rotatable workpiece receiving devices is non-rotatably disposed in the chamber. However, it is also definitely possible to arrange this transport element rotatably with respect to the axis of the carrousel but independently of the latter, whereby, for example, by means of such a transport element, several exterior openings may be serviced, whereas, in the preferred embodiment according to claim 4, one transport element, which is disposed in a non-rotatable manner, must be assigned to each exterior opening to be serviced by it.
In the case of a chamber with the carrousel or in the case of a chamber combination with this chamber on the latter, or on a chamber combination with a chamber in the case of which the transport element is constructed to be rotationally movable and linearly displaceable, it is achieved according to the approach of claim 5 that a workpiece which travels through this chamber toward a treatment and then travels back through this chamber from the treatment, remains much longer in the chamber on the way there than on the way back. As a result, a conditioning of the workpieces in this chamber becomes possible before their treatment, such as a degasification, for the purpose of which the mentioned chamber may definitely be heated or another pretreatment process may be used.
Mainly the chamber with the carrousel is preferred for this purpose because, in this case, a significantly larger number of workpiece receiving devices may be provided on the carrousel than on the chamber on which the transport element is disposed in a rotationally movable as well as linearly movable manner, specifically with much lower expenditures, if it is considered that the enlargement of the carrousel is only a question of the chamber dimension, whereas the multiplying of the rotationally and linearly movable transport elements results in a significant increase of the complexity of the chamber.
On the chamber with the carrousel as well as on the chamber with the rotationally and linearly moved transport element and thus also on the chamber combination, it is preferred according to claim 6 to design at least one transport element so that it can be moved out and back at a right angle with respect to the pertaining axis of rotation. This consequently maintains the two-dimensionality of the transport path, whether this is in addition to the two-dimensional transport path with the carrousel or in addition to the rotating movement and thus to the two-dimensional movement of the transport element.
Although it is easily possible to arrange on all chambers or chamber combinations described here disk-shaped workpieces with their disk face in the respective rotating planes, and thus to arrange the workpiece receiving devices correspondingly, it is preferred according to claim 7 to arrange for such disk-shaped workpieces the workpiece receiving device in such a manner that its receiving surface during the rotation, whether of the carrousel or of the transport element, sweeps over a cylindrical surface.
The chamber with the carrousel or a chamber combination with this carrousel chamber is also preferably constructed according to claim 8.
As a result, it is achieved in a constructively simple manner that the carrousel drive and the drive of the additional transport element, whether this is a rotational and radial drive or only a radial drive, can be separated in the chamber in a space-saving manner.
The above-mentioned chamber with the carrousel, also in the above-mentioned combination, is also preferably constructed according to claim 9.
As a result of the fact that the receiving devices are disposed in a radially springy manner, they may, if they are aligned to an exterior opening to be serviced, be placed against the opening border by means of the transport element until a vacuum-tight closure is achieved, whereby, viewed from the interior of the chamber, the workpiece receiving device on the mentioned opening is situated outside the chamber while the opening closure is tight, and the mentioned workpiece receiving device can therefore be serviced from the outside of the chamber by the inserting or removing of a workpiece without any undesirable impairment of the atmosphere in the respective chamber.
Furthermore, controlled holding elements are provided particularly on the workpiece receiving devices of the chamber with the carrousel according to claim 10, in which case it should be explicitly mentioned, however, that such holding elements may also be provided on the workpiece receiving device on the transport element which may be provided in a rotationally movable as well as in a linearly movable manner.
In a further preferred variant according to claim 11, it is provided on the chamber with the carrousel or on the chamber with the linearly and radially movable transport element of the combination that at least some of the exterior openings are tightly, preferably vacuum-tightly, closable by the effect of the at least one transport element.
In the case of the chamber with the carrousel, this is implemented by the at least one transport element which can be radially moved out and back; in the case of the chamber combination, it is implemented by the rotationally movable and linearly displaceable transport element.
If, in the case of the above-mentioned combination, a chamber with a carrousel and one with a linearly and rotationally movable transport element are combined, a respective common exterior opening of the chambers is closed off tightly, preferably vacuum-tightly, preferably by the transport element of one chamber as well as by that of the other chamber.
Depending on the requirement of the atmospheric uncoupling of the two chambers, a sealing may be sufficient by means of a gap sealing (diaphragm gland) in the sense of a pressure stage, or both chambers are separated in a vacuum-tight manner.
A vacuum treatment facility comprising a chamber with a carrousel or with the above-mentioned chamber combination is achieved according to claim 12.
The transport method according to the invention is achieved in claim 13 with preferred embodiments according to claim 14.